Furniture spring construction



Aug. 29, 1967 P. KOCH FURNITURE SPRING CONSTRUCTION 2 Sheets-Sheet 1 Filed June 15, 1966 i. lllll 1 l CNTOR P ER KOCH BY 1, I I

ATTORND S Aug. 29, 1967 P. KOCH FURNITURE SPRING CONSTRUCTION 2 Sheets-Sheet 2 Filed June 15, 1966 I5 2 IO INVENTOR PETE KOCH ATTORNEYS United States Patent 3,338,571 FURNITURE SPRING CONSTRUCTION Peter Koch, Vancouver, British Columbia, Canada, assignor to Tree Island Steel Co., Ltd., Tree Island, Richmond, British Columbia, Canada Filed June 13, 1966, Ser. No. 557,306 8 Claims. (Cl. 26799) This invention relates to furniture construction and in particular to spring construction therefor.

In the design of furniture, such as chairs of chesterfields, the construction of the springs therefore, particularly the seat springs, is of utmost importance. In order to obtain utmost comfort, the seat springs must be quite resilient, yet must give firm support for people of excessive weight and which, in its normal condition, must return a seat covering normally applied thereover to a flat eye-pleasing condition. As the furniture field is highly competitive, furniture designers have endeavoured to design a spring suspension which attains the desired results, yet which is not so costly to fabricate that the cost of such furniture is prohibitive. These endeavours have resulted in furniture spring design in which the entire spring is made up of a plurality of separate units which may be secured individually to the furniture frame, and which therefore permits the construction of furniture seats of any width, thereby permitting furniture to be constructed of any desired width by simply increasing or decreasing the number of units employed. However, in order to achieve the utmost in seating comfort and appearance, the cost factor has suffered.

The present invention provides a seat spring unit for furniture which is of the last-mentioned type and which, by embodying the principle of supporting a plurality of compression springs on a resilient base, is free to bend under the action of the compression springs when the latter are subject to the weight of a seated individual yet which provides a firm stable support, and furthermore which returns the springs and the seat covering thereo-ver to a normal flat condition.

The present invention further provides a seat spring construction of this type which is relatively inexpensive to manufacture and fabricate, and which is relatively easy to repair in event of damage. v

The present invention also provides a seat spring construction of this type in which the individual units thereof may be easily and quickly installed in the seat frame.

The present invention comprises a.pair of straight elongated resilient supporting elements arranged in spaced apart horizontally extending side by side relationship, a row of vertically disposed coil compression springs extending the length of the supporting elements, each spring being connected at its lower end to both said elements, connecting means for pivotally connecting one of the ends of each of the elements to a framing member on one side of the well, resilient stretchable means at the other end of the supporting elements for connecting the latter to a framing member on the opposite side of the well, and brace means extending between said other ends of said supporting elements for maintaining the latter in fixed spaced relationship.

In the drawings which illustrate the invention,

FIGURE 1 is a plan view of a seat with the covering thereof partially removed for purposes of clarification,

FIGURE 2 is an isometric view of an individual unit installed in a piece of furniture, I

FIGURE 3 is a side view of one individual unit in a normal or non-supporting condition, and

FIGURE 4 is a view similar to FIGURE 3 of an individual unit under a loaded condition.

Referring to the drawings and in particular to FIG- URES 1 and 2 thereof, there is illustrated a seat frame 10 which is generally of rectangular outline dependent of course upon the shape and width of the furniture involved. This frame has front 11 and back 12 frame members spaced apart by side members 13, thereby forming a seat spring well. In the frame illustrated, the front member 11 is of two piece construction formed of a pair of wooden members of rectangular cross sectional shape, one of them 14 being on edge while the other 15 is on its side adjacent the lower edge of the former.

Referring now to FIGURE 2, there is illustrated a seat spring unit 16. This unit comprises a supporting base 17 which is formed of an elongated spring steel rod bent into substantially a U-shape so as to present a pair of elongated spacedly parallel legs 18 and 19, and a base member 20 extending transversely therebetween, the latter being bent slightly at its juncture with said legs 18 and 19 to form re-entrant corner slots or loops 22. The free ends of the legs 18 and 19 are bent inwardly and backwardly to form hook elements 23 and 24 respectively.

The supporting base 17 is secured to the front frame member 11 by means of a connector 26. This connector is formed of sheet metal and is generally shaped having an upper base plate 27 and side plates 28. The base plate extends at one end beyond the side plates and has a right angularly bent end portion 29, whereas the side plates 28 have right angularly extending flange portions 30 formed at their lower edges. This right angularly bent end portion 29 is arranged to overlie the front member 14 while the flange portion 30 rests upon the other member 15. Said end portion 29 and flange portion 30 are also provided with holes 31 by means of which the connector 26 may be fastened to the front member 11 by means of screws. The side plates 28 have extended side portions 32 in each of which holes 33 are formed which pivotally and slidably receive the hook elements 23 and v 24 of the supporting base 17.

The supporting base is also connected to the back member 12, the connection being achieved by means of a pair of coil tension springs 35 and 36 which are engaged with the base member 20 at the corner slots 22. These tensions springs 35 and 36 are secured to flat metallic strap elements 37 and 38 respectively, the latter being secured by screws to the back frame member 12. The length of the legs 18 and 19 of the supporting base 17 are such that when connected as hereinbefore described to both the front and back frame members 11 and 12, the tension springs 35 and 36 are slightly stretched so as to maintain the supporting base 17 in a substantially horizontal position.

This supporting base serves as a support for a plurality of helically shaped double cone compression springs 40. These compression springs are of known construction and are types of springs most generally used in the furniture trade. These compression springs 40 are arranged in a vertical position and spaced apart equidistantly along the length of the legs 18 and 19, and are secured at their lower ends as by clips 42 to both-of said legs.

In order to restrain independent lateral and fore and aft movement of the compression springs 40, the seat spring unit 16 is provided with an upper connecting frame 44. This frame is formed of a continuous flat steel spring ribbon arranged so that the frame is of elongated rectangular shape having spaced side members 45 and end members 46. The frame 44 is arranged over the compression springs 40 and the side members 45 connected thereto as with clips 49. This frame extends over the connector 26 and a small conical helical compression spring 50 inserted therebetween, being connected by clips 52 at its upper end to said frame and at its lower end by clips 53 to the upper plate 27 of the connector.

The steel ribbon forming the frame 44 is arranged with a flat side uppermost so as to permit individual depression of the coil springs 40 so as to restrain individual lateral and fore and aft movement thereof.

The seat spring unit 16 is arranged on the frame as illustrated in FIGURE 1 in side by side relationship with spring units of identical nature, the number of spring units used being dependent of course upon the width of the piece of furniture involved. The frames 44 of each of said units are then interconnected by a steel ribbon 55 of the same cross sectional configuration as the steel ribbon forming the frame 44. The connection may be made by way of clips or the like, and serves to restrain individual movement of each unit relative to the units adjacent.

The operating characteristics of the seat spring unit 16 may be best described with reference to FIGURES 3 and 4 of the drawings.

In FIGURE 3, the seat spring unit is illustrated in its normal condition when not supporting the weight of an individual. In this condition, the tension of the tension springs 35 and 36 and the resilient action of the supporting base 17 tend to hold the legs 18 and 19 of the latter in a horizontally extending non-flexed position so that the upper ends of the coil springs 40 lie in a common horizontal plane forming a firm flat base for a cushion or the like with which most chairs and chesterfields are supplied. Upon being loaded by the weight of a seated individual, the coil springs 40 will be slightly compressed and also transfer the weight of the individual to the supporting base 17. The pivotal connection of the legs 18 and 19 with the connector 26 and the connection of said base 17 via the tension springs 35 and 36 to the back frame member 12 also permit the legs to flex. The total deflection of the entire unit therefore is the combined deflection of the coil springs 40, the deflection of the supporting base 17 and the flexure of the tension springs 35 and 36. This will, consequently, enable the manufacturer to employ coil springs 40 of reduced depth without sacrificing seating comfort, yet at the same time improving the stability of the entire seat spring unit.

It will be further appreciated that the seat spring unit constructed as above, is relatively inexpensive to fabricate, but is amenable to being made up in varied lengths, dependent upon the size of the pieces of furniture involved. The supporting base is easily and quickly formed from a single length of steel spring rod, and the legs 18 and 19 thereof may therefore be varied at will to suit the type and size of furniture to which the spring unit is to be employed without altering production procedures. Repairs which are sometimes necessary with furniture of this type, may also be easily and quickly made as the component parts of the seat spring unit are easily separable, thereby facilitating the replacement of any damaged component.

What I claim as my invention is:

1. A spring seat assembly for furniture, the latter having spaced apart framing members arranged to form a seat spring well, comprising an elongated thin rod formed of springy high yield strength material and bent to a U- shape so as to form a pair of elongated legs and a connecting base, a row of vertically disposed coil compression springs extending the length of the legs, each spring being connected at its lower end to both of said legs, connecting means for pivotally connecting the free ends of the legs in spaced apart relationship to a framing member on one side of the seat well, and resilient stretchable means at the other ends of the legs for connecting the latter to a framing member on the other side of the well.

2. A spring seat assembly as claimed in claim 1 including means for interconnecting the coil springs at the upper ends thereof so as to restrain said upper ends against independent lateral movement.

3. A spring seat assembly as claimed in claim 2 in which said last-mentioned means comprises an elongated rectangular open frame formed of a continuous ribbon of spring steel, said frame having spaced apart side members, each of said side members being connected to each of the springs in said row.

4. A spring seat assembly as claimed in claim 1 in which said connecting means comprises a U-shaped con nector element having a pair of spaced apart longitudinally extending side portions, the latter each being provided with an opening, said connecting element being detachably secured to said one framing member and wherein each of said legs has an inwardly and backwardly bent free end portion for engaging an extending side portion at said opening.

5. A spring seat assembly as claimed in claim 1 wherein the resilient stretchable means comprises a pair of coil tension springs.

6. A spring seat assembly for furniture, the latter having spaced apart framing members arranged to form a seat spring well, comprising an elongated thin rod formed of springy high yield strength material and bent to a U- shape so as to form a pair of elongated legs and a connecting base, a plurality of vertically disposed independently compressible spring elements having upper and lower ends arranged in a row longitudinally of the legs, each element being connected at its lower end to both of the legs, connecting means for pivotally connecting one end of each leg to a framing member on one side of the seat well and resilient stretchable means at the other ends of the legs for connecting the latter to a framing member on the other side of the well.

7. A spring seat assembly as claimed in claim 6 in which the spring elements comprise coil compression springs.

8. A spring seat assembly as claimed in claim 6 including means for interconnecting the spring elements at the upper ends thereof so as to restrain said upper ends against independent lateral movement.

References Cited UNITED STATES PATENTS 1,854,681 4/1932 Wilson 26799 2,101,054 12/1937 Eaton 26799 3,006,629 10/1961 Snykin et a1. 26799 ARTHUR L. LA POINT, Primary Examiner, 

1. A SPRING SEAT ASSEMBLY FOR FURNITURE, THE LATTER HAVING SPACED APART FRAMING MEMBERS ARRANGED TO FORM A SEAT SPRING WELL, COMPRISING AN ELONGATED THIN ROD FORMED OF SPRINGY HIGH YIELD STRENGTH MATERIAL AND BENT TO A USHAPE SO AS TO FORM A PAIR OF ELONGATED LEGS AND A CONNECTING BASE, A ROW OF VERTICALLY DISPOSED COIL COMPRESSION SPRINGS EXTENDING THE LENGTH OF THE LEGS, EACH SPRING BEING CONNECTED AT ITS LOWER END TO BOTH OF SAID LEGS, CONNECTING MEANS FOR PIVOTALLY CONNECTING THE FREE ENDS OF THE LEGS IN SPACED APART RELATIONSHIP TO A FRAMING MEMBER ON ONE SIDE OF THE SEAT WELL, AND RESILIENT STRETCHABLE MEANS AT THE OTHER ENDS OF THE LEGS FOR CONNECTING THE LATTER TO A FRAMING MEMBER ON THE OTHER SIDE OF THE WELL. 